On 2/9/24 12:30 PM, Bart Van Assche wrote:
> Originally io_cancel() only supported cancelling USB reads and writes.
> If I/O was cancelled successfully, information about the cancelled I/O
> operation was copied to the data structure the io_cancel() 'result'
> argument points at. Commit 63b05203af57 ("[PATCH] AIO: retry
> infrastructure fixes and enhancements") changed the io_cancel() behavior
> from reporting status information via the 'result' argument into
> reporting status information on the completion ring. Commit 41003a7bcfed
> ("aio: remove retry-based AIO") accidentally changed the behavior into
> not reporting a completion event on the completion ring for cancelled
> requests. This is a bug because successful cancellation leads to an iocb
> leak in user space. Since this bug was introduced more than ten years
> ago and since nobody has complained since then, remove support for I/O
> cancellation. Keep support for cancellation of IOCB_CMD_POLL requests.
This is hilarious! But also great news, as we can just kill it with
fire. For the patch:
Reviewed-by: Jens Axboe <axboe@xxxxxxxxx>
--
Jens Axboe
